(The statements shown test for hostile sexism; others testing for benevolent sexism include Women have a superior moral sensibility and so on.)

The inventory was administered in the students' classrooms. Two to four weeks later the same students were (seemingly unrelatedly) exposed to a number of short role-playing scenarios. Buried in the middle of those were one of the following:

Sexist humour condition: A vignette consisting of various characters exchanging mostly sexist jokes (How can you tell if a blonde's been
using the computer? There's White-Out on the screen!).

Neutral humour condition: A vignette consisting of various characters exchanging neutral jokes (What's the difference between a golfer and a skydiver? A golfer goes whack — Damn![...]).

Sexist statement condition: A vignette consisting of various characters exchanging sexist social commentary (I just think that a woman's place is in the
home and that it's a woman's role to do domestic duties
such as laundry for her man.).

(Pretest ratings indicated that the sexist jokes were considered just as funny as the neutral ones, and just as sexist as the sexist statements.)

Within the context of the role-play, the students were then asked how much of a fixed budget they would be willing to donate to a fictional women's organisation.

Result: In the sexist humour condition, students' hostile sexism levels predicted how little they would donate.
However, in the other two conditions, students' hostile sexism levels did not affect donation amounts.

So what does that mean?

According to the authors:

These findings cannot easily be explained as merely a
priming effect apart from the role of humor...
For people high in prejudice, humorous disparagement can create the perception of a shared norm
of tolerance of discrimination that may be used to guide
their own responses in the immediate context.

In other words, sexist humor can serve as a releaser of prejudice. People with internalised sexism don't necessarily always act upon it, but they're far more likely to when other people are joking and creating a safe environment for them to freely act upon those values.

(Omitted: discussion of the second experiment in the paper which addresses some methodological issues with the above experiment (e.g. imagined versus real social groups; imagined versus real money).

Also omitted: the usual discussion about how representative undergrad sociology students are of their society at large.)

IRL takeaways

Even if you think you are not particularly bigoted yourself, making jokes at the expense of a marginalised group is absolutely not a morally neutral action. (No, not just gender.)

(Obviously this assumes you believe that further marginalising marginalised groups is ceterus paribus bad. If you don't, that's a whole other discussion. Several whole other discussions.)

Jokes do not exist in a vacuum; they coexist with culture. Jokes are not just a byproduct of culture, they influence culture.

That thing they said in primary school about not making fun of other people? Still relevant.

About the Author

Chris Chen is a self-styled human being who enjoys philosophy, music composition, rants about kyriarchy, Tumblrs full of shiny pictures, abstract maths, programming, surreptitious narcissism, and other things besides.

Born in Melbourne and based in Sydney, she's not, whatever her display picture suggests, a Japanese creation goddess reincarnated as a wolf.